Basic study on the effect of nasally administered salmon calcitonin preparation on the nasal ciliary epithelium

Nasal administration of drugs is an administration method which is worthy of attention. In such therapy, local administration should not damage the nasal mucous membranes. In the present study, we conducted an investigation by the tissue culture test method of the functional and morphological effects of new nasal calcitonin preparation, which is being developed as a nasal spray agent for osteoporosis, on the nasal ciliary epithelium. The nasal septal mucous membranes of C3H-strain mice were used, and 5 types of nasal calcitonin preparations with a microcrystalline cellulose base and additives added were used. The various drugs were added to nasal mucous membrane slices in RPMI-1640 culture medium; ciliary activity before addition and 0.5, 2, and 4 hr after was electrophotometrically measured; and morphological observation was then carried out by SEM. In the various additive groups, virtually no effect on ciliary activity was observed, and the same results were obtained when 3 and 9 times the estimated clinical spray dosage was added. Moreover, in morphological observation by SEM, in the various additive groups, no morphological changes in samples of nasal ciliary specimens were observed after 4 hr of culturing at the maximum administered dosage (9 times the estimated clinical spray dosage). Based on these findings, it was concluded that the series of calcitonin preparations with various additives had no hazardous effect on the nasal ciliary epithelium.